Queen Elsa of Arendelle (also known as the Snow Queen) is the firstborn daughter of former monarchs King Agnarr and Queen Iduna, older sister of Princess Anna, and the contemporary ruler of Arendelle. Her powers over ice and snow ultimately led her to become the Snow Queen at adulthood.
How Frozen Should Have Ended
At the trolls' home, Grand Pabbie explains that Elsa's powers, despite being beautiful, have great danger, and warns her that fear will be her enemy. Her parents, however, don't realize that love is the answer to controlling her powers and keep getting wrong interpretations, much to Pabbie's irritation. He takes the royal family to Professor X, who offers to teach Elsa.
Years later, Elsa has embraced her powers and sings with her classmates.
How Logan Should Have Ended
Elsa is present among the X-Men as they sing in honor of Logan.